Paul Eggert [Sun, 19 Apr 2015 08:06:33 +0000 (01:06 -0700)]
Better fix for setenv (..., NULL, ...)
* stdlib/setenv.c (__add_to_environ):
Dump core quickly if setenv (..., NULL, ...) is called.
This time, do it the right way, and pacify GCC with a pragma.
Chris Metcalf [Thu, 16 Apr 2015 13:40:21 +0000 (09:40 -0400)]
tile: Enable PI_STATIC_AND_HIDDEN
This does make ld.so very slightly larger (0.3%) and doesn't seem to
actually improve performance; in fact, my limited testing suggested a
slight (0.1%) performance decrease (running fork/exec of a no-op program
in a loop), but I didn't do enough testing to establish statistical
significance.
However, Roland agrees that it makes sense to switch tile to using
this path, since it's the more standard way.
This patch fix the static build for strftime, which uses __wcschr.
Current powerpc32 implementation defines the __wcschr be an alias to
__wcschr_ppc32 and current implementation misses the correct alias for
static build.
It also changes the default wcschr.c logic so a IFUNC implementation
should just define WCSCHR and undefine the required alias/internal
definitions.
Stefan Liebler [Mon, 13 Apr 2015 19:23:10 +0000 (21:23 +0200)]
Use correct signedness in wcsncmp
[BZ #18206]
* wcsmbs/wcsncmp.c (wcsncmp): Compare as wchar_t, not wint_t.
Use signed comparision instead of substraction to avoid
overflow bug.
* localedata/tests-mbwc/tst_wcsncmp.c (tst_wcsncmp):
Take the sign of ret.
* localedata/tests-mbwc/dat_wcsncmp.c (tst_wcsncmp_loc):
Do not expect precise return values. Only the sign matters.
* wcsmbs/Makefile (strop-tests): Add wcsncmp.
* wcsmbs/test-wcsncmp.c: New File.
* string/test-strncmp.c: Add wcsncmp support.
Stefan Liebler [Mon, 13 Apr 2015 19:16:56 +0000 (21:16 +0200)]
Set errno for log1p on pole/domain error.
According to bug 6792, errno is not set to ERANGE/EDOM
by calling log1p/log1pf/log1pl with x = -1 or x < -1.
This patch adds a wrapper which sets errno in those cases
and returns the value of the existing __log1p function.
The log1p is now an alias to the wrapper function
instead of __log1p.
The files in sysdeps are reflecting these changes.
The ia64 implementation sets errno by itself,
thus the wrapper-file is empty.
The libm-test is adjusted for log1p-tests to check errno.
Stefan Liebler [Fri, 10 Apr 2015 22:42:00 +0000 (15:42 -0700)]
Update tst_mbrlen/tst_mbrtowc for mblen change
commit 9781a370023952383028e07399fd196a889bb2be changed the expected
results for mbrlen in case of passing n=0 to -2. The initialization of
tst_mbrlen_loc and tst_mbrtowc should be updated accordingly.
* tests-mbwc/dat_mbrlen.c (tst_mbrlen_loc): Change expected
result to -2 in case of n == 0.
* tests-mbwc/tst_mbrtowc.c (tst_mbrtowc): Check result against
-2 instead of 0.
Joseph Myers [Fri, 10 Apr 2015 20:45:30 +0000 (20:45 +0000)]
Fix strtof decimal rounding close to half least subnormal (bug 18247).
Bug 18247 is an off-by-one error in strtof's determination of a
decimal exponent such that any value with that decimal exponent is at
most half the least subnormal and so the appropriate underflowing
value for the rounding mode can be determined with no
multiple-precision computations. (Whether the value is in fact safe
despite the off-by-one depends on the floating-point format in
question. It's wrong for float and for m68k ldbl-96 but not for other
supported formats.) This patch corrects the computation of the
exponent in question to be safe in general, adding a comment
explaining the new computation.
Tested for x86_64.
[BZ #18247]
* stdlib/strtod_l.c (____STRTOF_INTERNAL): Decrease minimum
decimal exponent by 1.
* stdlib/tst-strtod-round-data: Add more tests.
* stdlib/tst-strtod-round.c (tests): Regenerated.
The dbl-64 implementation of atan2 does computations that expect to
run in round-to-nearest mode, and in other modes the errors can
accumulate to more than the maximum accepted 9ulp. This patch makes
it use FE_TONEAREST internally, similar to other functions with such
issues. Tests that previously produced large errors are added for
atan2 and the closely related carg, clog and clog10 functions.
Tested for x86_64 and x86 and ulps updated accordingly.
[BZ #18210]
[BZ #18211]
* sysdeps/ieee754/dbl-64/e_atan2.c: Include <fenv.h>.
(__ieee754_atan2): Set FE_TONEAREST mode for internal
computations.
* math/auto-libm-test-in: Add more tests of atan2, carg, clog and
clog10.
* math/auto-libm-test-out: Regenerated.
* sysdeps/i386/fpu/libm-test-ulps: Update.
* sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
Joseph Myers [Wed, 8 Apr 2015 17:14:12 +0000 (17:14 +0000)]
Fix dbl-64 atan in non-default rounding modes (bug 18197).
The dbl-64 implementation of atan does computations that expect to run
in round-to-nearest mode, and in other modes the errors can accumulate
to more than the maximum accepted 9ulp. This patch makes it use
FE_TONEAREST internally, similar to other functions with such issues.
Tested for x86_64 and x86; no ulps updates needed.
[BZ #18197]
* sysdeps/ieee754/dbl-64/s_atan.c: Include <fenv.h>.
(atan): Set FE_TONEAREST mode for internal computations.
* math/auto-libm-test-in: Add more tests of atan.
* math/auto-libm-test-out: Regenerated.
math/test-fenvinline: Cast fe_exc to unsigned int before printing
On Alpha and IA-64, fexcept_t is unsigned long. But all the values
fit within an int, so the cast is ok for printing. All other hosts
use unsigned int or unsigned short already.
malloc: Consistently apply trim_threshold to all heaps [BZ #17195]
Trimming heaps is a balance between saving memory and the system overhead
required to update page tables and discard allocated pages. The malloc
option M_TRIM_THRESHOLD is a tunable that users are meant to use to decide
where this balance point is but it is only applied to the main arena.
For scalability reasons, glibc malloc has per-thread heaps but these are
shrunk with madvise() if there is one page free at the top of the heap.
In some circumstances this can lead to high system overhead if a thread
has a control flow like
while (data_to_process) {
buf = malloc(large_size);
do_stuff();
free(buf);
}
For a large size, the free() will call madvise (pagetable teardown, page
free and TLB flush) every time followed immediately by a malloc (fault,
kernel page alloc, zeroing and charge accounting). The kernel overhead
can dominate such a workload.
This patch allows the user to tune when madvise gets called by applying
the trim threshold to the per-thread heaps and using similar logic to the
main arena when deciding whether to shrink. Alternatively if the dynamic
brk/mmap threshold gets adjusted then the new values will be obeyed by
the per-thread heaps.
Bug 17195 was a test case motivated by a problem encountered in scientific
applications written in python that performance badly due to high page fault
overhead. The basic operation of such a program was posted by Julian Taylor
https://sourceware.org/ml/libc-alpha/2015-02/msg00373.html
With this patch applied, the overhead is eliminated. All numbers in this
report are in seconds and were recorded by running Julian's program 30
times.
pyarray
glibc madvise
2.21 v2
System min 1.81 ( 0.00%) 0.00 (100.00%)
System mean 1.93 ( 0.00%) 0.02 ( 99.20%)
System stddev 0.06 ( 0.00%) 0.01 ( 88.99%)
System max 2.06 ( 0.00%) 0.03 ( 98.54%)
Elapsed min 3.26 ( 0.00%) 2.37 ( 27.30%)
Elapsed mean 3.39 ( 0.00%) 2.41 ( 28.84%)
Elapsed stddev 0.14 ( 0.00%) 0.02 ( 82.73%)
Elapsed max 4.05 ( 0.00%) 2.47 ( 39.01%)
glibc madvise
2.21 v2
User 141.86 142.28
System 57.94 0.60
Elapsed 102.02 72.66
Note that almost a minutes worth of system time is eliminted and the
program completes 28% faster on average.
To illustrate the problem without python this is a basic test-case for
the worst case scenario where every free is a madvise followed by a an alloc
/* gcc bench-free.c -lpthread -o bench-free */
static int num = 1024;
for (i = num; i--;)
{
void *m = malloc (48*4096);
dostuff (m);
free (m);
}
return NULL;
}
int main()
{
int i;
pthread_t t;
void *ret;
if (pthread_create (&t, NULL, worker, NULL))
exit (2);
if (pthread_join (t, &ret))
exit (3);
return 0;
}
Before the patch, this resulted in 1024 calls to madvise. With the patch applied,
madvise is called twice because the default trim threshold is high enough to avoid
this.
This a more complex case where there is a mix of frees. It's simply a different worker
function for the test case above
void *worker (void *data)
{
int i;
int j = 0;
void *free_index[num];
for (i = num; i--;)
{
void *m = malloc ((i % 58) *4096);
dostuff (m);
if (i % 2 == 0) {
free (m);
} else {
free_index[j++] = m;
}
}
for (; j >= 0; j--)
{
free(free_index[j]);
}
return NULL;
}
glibc 2.21 calls malloc 90305 times but with the patch applied, it's
called 13438. Increasing the trim threshold will decrease the number of
times it's called with the option of eliminating the overhead.
ebizzy is meant to generate a workload resembling common web application
server workloads. It is threaded with a large working set that at its core
has an allocation, do_stuff, free loop that also hits this case. The primary
metric of the benchmark is records processed per second. This is running on
my desktop which is a single socket machine with an I7-4770 and 8 cores.
Each thread count was run for 30 seconds. It was only run once as the
performance difference is so high that the variation is insignificant.
Note that the saving happens to be a concidence as the size allocated
by ebizzy was less than the default threshold. If a different number of
chunks were specified then it may also be necessary to tune the threshold
to compensate
This is roughly quadrupling the performance of this benchmark. The difference in
system CPU usage illustrates why.
ebizzy running 1 thread with glibc 2.21
10230 records/s 306904
real 30.00 s
user 7.47 s
sys 22.49 s
22.49 seconds was spent in the kernel for a workload runinng 30 seconds. With the
patch applied
ebizzy running 1 thread with patch applied
44126 records/s 1323792
real 30.00 s
user 29.97 s
sys 0.00 s
system CPU usage was zero with the patch applied. strace shows that glibc
running this workload calls madvise approximately 9000 times a second. With
the patch applied madvise was called twice during the workload (or 0.06
times per second).
2015-02-10 Mel Gorman <mgorman@suse.de>
[BZ #17195]
* malloc/arena.c (free): Apply trim threshold to per-thread heaps
as well as the main arena.
H.J. Lu [Tue, 31 Mar 2015 20:17:51 +0000 (13:17 -0700)]
Limit threads sharing L2 cache to 2 for SLM/KNL
Silvermont and Knights Landing have a modular system design with two cores
sharing an L2 cache. If more than 2 cores are detected to shared L2 cache,
it should be adjusted for Silvermont and Knights Landing.
[BZ #18185]
* sysdeps/x86_64/cacheinfo.c (init_cacheinfo): Limit threads
sharing L2 cache to 2 for Silvermont/Knights Landing.
H.J. Lu [Tue, 31 Mar 2015 12:15:43 +0000 (05:15 -0700)]
Add ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA to x86
With copy relocation, address of protected data defined in the shared
library may be external. When there is a relocation against the
protected data symbol within the shared library, we need to check if we
should skip the definition in the executable copied from the protected
data. This patch adds ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA and defines
it for x86. If ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA isn't 0, do_lookup_x
will skip the data definition in the executable from copy reloc.
[BZ #17711]
* elf/dl-lookup.c (do_lookup_x): When UNDEF_MAP is NULL, which
indicates it is called from do_lookup_x on relocation against
protected data, skip the data definion in the executable from
copy reloc.
(_dl_lookup_symbol_x): Pass ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA,
instead of ELF_RTYPE_CLASS_PLT, to do_lookup_x for
EXTERN_PROTECTED_DATA relocation against STT_OBJECT symbol.
* sysdeps/generic/ldsodefs.h * (ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA):
New. Defined to 4 if DL_EXTERN_PROTECTED_DATA is defined,
otherwise to 0.
* sysdeps/i386/dl-lookupcfg.h (DL_EXTERN_PROTECTED_DATA): New.
* sysdeps/i386/dl-machine.h (elf_machine_type_class): Set class
to ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA for R_386_GLOB_DAT.
* sysdeps/x86_64/dl-lookupcfg.h (DL_EXTERN_PROTECTED_DATA): New.
* sysdeps/x86_64/dl-machine.h (elf_machine_type_class): Set class
to ELF_RTYPE_CLASS_EXTERN_PROTECTED_DATA for R_X86_64_GLOB_DAT.
Alan Modra [Thu, 26 Mar 2015 02:00:45 +0000 (12:30 +1030)]
Harden powerpc64 elf_machine_fixup_plt
IFUNC is difficult to correctly implement on any target needing a GOT
to support position independent code, due to the dependency on order
of dynamic relocations. ld.so should be changed to apply IFUNC
relocations last, globally, because without that it is actually
impossible to write an IFUNC resolver in C that works in all
situations. Case in point, vfork in libpthread.so is an IFUNC with
the resolver returning &__libc_vfork. (system and fork are similar.)
If another shared library, libA say, uses vfork then it is quite
possible that libpthread.so hasn't been dynamically relocated before
the unfortunate libA is dynamically relocated. In that case the GOT
entry for &__libc_vfork is still zero, so the IFUNC resolver returns
NULL. LD_BIND_NOW=1 results in libA PLT dynamic relocations being
applied using this NULL value and ld.so segfaults.
This patch hardens ld.so to not segfault on a NULL from an IFUNC
resolver. It also fixes a problem with undefined weak. If you leave
the plt entry as-is for undefined weak then if the entry is ever
called it will loop in ld.so rather than segfaulting.
* sysdeps/powerpc/powerpc64/dl-machine.h (elf_machine_fixup_plt):
Don't segfault if ifunc resolver returns a NULL. Do set plt to
zero for undefined weak.
(elf_machine_plt_conflict): Similarly.
Joseph Myers [Wed, 25 Mar 2015 21:21:18 +0000 (21:21 +0000)]
Remove unused macros from i386 lowlevellock.h.
In the course of the work on six-argument syscalls I noticed that the
i386 lowlevellock.h contained some unused macro definitions (already
unused before my patch). This patch removes them.
Tested for x86 that installed stripped shared libraries are unchanged
by this patch.
Joseph Myers [Wed, 25 Mar 2015 15:17:54 +0000 (15:17 +0000)]
Support six-argument syscalls from C for 32-bit x86, use generic lowlevellock-futex.h (bug 18138).
This patch follows the approach outlined in
<https://sourceware.org/ml/libc-alpha/2015-03/msg00656.html> to
support six-argument syscalls from INTERNAL_SYSCALL for 32-bit x86,
making them call a function __libc_do_syscall that takes the syscall
number and three syscall arguments in the registers in which the
kernel expects them, along with a pointer to a structure containing
the other three arguments.
In turn, this allows the generic lowlevellock-futex.h to be used on
32-bit x86, so supporting lll_futex_timed_wait_bitset (and so allowing
FUTEX_CLOCK_REALTIME to be used in various cases, so fixing bug 18138
for 32-bit x86 and leaving hppa as the only architecture missing
lll_futex_timed_wait_bitset). The change to lowlevellock.h's
definition of SYS_futex is because the generic lowlevelloc-futex.h
ends up bringing in bits/syscall.h which defines SYS_futex to
__NR_futex, so resulting in redefinition errors. The revised
definition in lowlevellock.h is in line with what the x86_64 version
does.
__libc_do_syscall is only needed in libpthread at present (meaning
nothing special needs to be done to make it shared-only in most
libraries containing it, static in libc only, as on ARM).
Tested for 32-bit x86, with the glibc testsuite and with the test in
bug 18138. The failures seen
FAIL: nptl/tst-cleanupx4
FAIL: rt/tst-cpuclock2
are pre-existing.
[BZ #18138]
* sysdeps/unix/sysv/linux/i386/sysdep.h (struct
libc_do_syscall_args): New structure.
(INTERNAL_SYSCALL_MAIN_0): New macro.
(INTERNAL_SYSCALL_MAIN_1): Likewise.
(INTERNAL_SYSCALL_MAIN_2): Likewise.
(INTERNAL_SYSCALL_MAIN_3): Likewise.
(INTERNAL_SYSCALL_MAIN_4): Likewise.
(INTERNAL_SYSCALL_MAIN_5): Likewise.
(INTERNAL_SYSCALL_MAIN_6): Likewise. Call __libc_do_syscall.
(INTERNAL_SYSCALL): Define to use INTERNAL_SYSCALL_MAIN_##nr.
Replace conditional definitions by conditional definitions of ....
(INTERNAL_SYSCALL_MAIN_INLINE): ... this. New macro.
* sysdeps/unix/sysv/linux/i386/libc-do-syscall.S: New file.
* sysdeps/unix/sysv/linux/i386/Makefile [$(subdir) = nptl]
(libpthread-sysdep_routines): Add libc-do-syscall.
* sysdeps/unix/sysv/linux/i386/lowlevellock-futex.h: Remove file.
* sysdeps/unix/sysv/linux/i386/lowlevellock.h (SYS_futex): Define
to __NR_futex not 240.
Alan Modra [Wed, 25 Mar 2015 05:23:47 +0000 (15:53 +1030)]
powerpc __tls_get_addr call optimization
This patch is glibc support for a PowerPC TLS optimization, inspired
by Alexandre Oliva's TLS optimization for other processors,
http://www.lsd.ic.unicamp.br/~oliva/writeups/TLS/RFC-TLSDESC-x86.txt
In essence, this optimization uses a zero module id in the tls_index
GOT entry to indicate that a TLS variable is allocated space in the
static TLS area. A special plt call linker stub for __tls_get_addr
checks for such a tls_index and if found, returns the offset
immediately. The linker communicates the fact that the special
__tls_get_addr stub is used by setting a bit in the dynamic tag
DT_PPC64_OPT/DT_PPC_OPT. glibc communicates to the linker that this
optimization is available by the presence of __tls_get_addr_opt.
tst-tlsmod2.so is built with -Wl,--no-tls-get-addr-optimize for
tst-tls-dlinfo, which otherwise would fail since it tests that no
static tls is allocated. The ld option --no-tls-get-addr-optimize has
been available since binutils-2.20 so doesn't need a configure test.
Alan Modra [Wed, 25 Mar 2015 05:15:36 +0000 (15:45 +1030)]
powerpc64 configure message
This feature doesn't depend on the linker, as can be seen from the
actual test. It's a compiler feature.
* sysdeps/powerpc/powerpc64/configure.ac: Correct "linker support
for overlapping .opd entries" to "support...".
* sysdeps/powerpc/powerpc64/configure: Regenerate
Joseph Myers [Tue, 24 Mar 2015 23:30:19 +0000 (23:30 +0000)]
Regenerate x86_64, x86 ulps from scratch.
The x86_64 and x86 libm-test-ulps files hadn't been regenerated from
scratch for some time, as evidenced by the presence of entries for
*_tonearest functions (those tests duplicated the
default-rounding-mode tests, and such duplicates are no longer run).
The aarch64, alpha, hppa, ia64, m68k, microblaze, powerpc, s390, sh,
sparc, tile files similarly could do with from-scratch regeneration as
evidenced by the presence of such entries. (Truncate the existing
file then run "make regen-ulps" and move the resulting file into
place.)
This patch regenerates the x86_64 and x86 files from scratch. It's
likely some of the reduced / removed ulps will need restoring because
they appear on processors or compiler versions other than the one I
tested on, but in such cases I'd like to first see if I can generate
new tests that show such ulps on the Intel processor I'm testing on,
to reduce the effects from different people using different processors
and compilers to regenerate the ulps.
Joseph Myers [Tue, 24 Mar 2015 23:06:28 +0000 (23:06 +0000)]
Add more tests of log2.
In testing for x86_64 on an AMD processor, I observed libm test
failures of the form:
testing long double (without inline functions)
Failure: Test: log2_downward (0x2.b7e151628aed4p+0)
Result:
is: 1.44269504088896356633e+00 0xb.8aa3b295c17f67600000p-3
should be: 1.44269504088896356622e+00 0xb.8aa3b295c17f67500000p-3
difference: 1.08420217248550443400e-19 0x8.00000000000000000000p-66
ulp : 1.0000
max.ulp : 0.0000
Maximal error of `log2_downward'
is : 1 ulp
accepted: 0 ulp
These issues arise because the maximum ulps when regenerating on one
processor are not the same as on another processor, so regeneration on
several processors may be needed when updating libm-test-ulps to avoid
failures for some users testing glibc - but such regeneration on
multiple processors is inconvenient. Causes can be: on x86 and, for
x86_64, for long double, variation in results of x87 instructions for
transcendental operations between processors; on x86, variation in
compiler excess precision between compiler versions and
configurations; on any processor where the compiler may contract
expressions using fused multiply-add, variation in what contraction
occurs.
Although it's hard to be sure libm-test-ulps covers all ulps that may
be seen in any configuration for the given architecture, in practice
it helps simply to add wider test coverage to make it more likely
that, when testing on one processor, the ulps seen are the biggest
that can be seen for that function on that processor, and hopefully
they are also the biggest that can be seen for that function in other
configurations for that architecture. Thus, this patch adds some
tests of log2 that increase the ulps I see on x86_64 on an Intel
processor, so that hopefully future from-scratch regenerations on that
processor will produce ulps big enough not to have errors from testing
on AMD processors. These tests were found by randomly generating
inputs and seeing what produced ulps larger than those currently in
libm-test-ulps. Of course such increases also improve the accuracy of
the empirical table of known ulps generated from libm-test-ulps files
that goes in the manual.
Tested for x86_64 and x86 and ulps updated accordingly.
* math/auto-libm-test-in: Add more tests of log2.
* math/auto-libm-test-out: Regenerated.
* sysdeps/i386/fpu/libm-test-ulps: Update.
* sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
Florian Weimer [Mon, 23 Mar 2015 15:34:48 +0000 (16:34 +0100)]
pthread_setaffinity (Linux variant): Rewrite to use VLA instead of alloca
extend_alloca was used to emulate VLA deallocation. The new version
also handles the res == 0 corner case more explicitly, by returning 0
instead of the (potentially undefined, but usually zero) system call
error.
Alan Modra [Thu, 19 Mar 2015 07:58:38 +0000 (18:28 +1030)]
Remove HAVE_ASM_PPC_REL16 references
In bc0cdc498 the configure check for HAVE_ASM_PPC_REL16 was removed
on the grounds that the minimum binutils supports rel16 relocs. This
is true, but not all references to HAVE_ASM_PPC_REL16 in the sources
were removed.
* config.h.in: Remove HAVE_ASM_PPC_REL16.
* sysdeps/powerpc/powerpc32/tls-macros.h: Remove HAVE_ASM_PPC_REL16
and false branch of conditional.
* sysdeps/unix/sysv/linux/powerpc/powerpc32/swapcontext-common.S:
Likewise.
Samuel Thibault [Sat, 21 Mar 2015 03:49:44 +0000 (04:49 +0100)]
Fix warnings
* sysdeps/mach/hurd/Makefile ($(common-objpfx)errnos.d): Depend on
libc-modules.h
* sysdeps/mach/hurd/i386/trampoline.c (_hurd_setup_sighandler): Remove
unused declaration of _hurd_intr_rpc_msg_in_trap.
* mach/mach_init.c (__mach_init): Test whether HAVE_HOST_PAGE_SIZE is
defined instead of whether it is non-zero.
* sysdeps/mach/hurd/i386/intr-msg.h (INTR_MSG_TRAP): Use "+m"
input constraint instead of both input and output constraint. Use ecx
clobber instead of %ecx.
* sysdeps/mach/hurd/malloc-machine.h (mutex_init, mutex_lock,
mutex_unlock): Use a statement expression instead of an expression list.
* sysdeps/mach/hurd/setitimer.c (_hurd_itimer_thread_stack_size): Set
type to vm_size_t instead of vm_address_t.
* sysdeps/mach/hurd/fork.c (__fork): Test whether STACK_GROWTH_UP is
defined instead of whether it is non-zero.
* hurd/hurd/ioctl.h (_hurd_locked_install_cttyid): New declaration.
* sysdeps/mach/hurd/setsid.c: Include <hurd/ioctl.h>.
* sysdeps/mach/hurd/mmap.c (__mmap): Use 0 instead of NULL for
comparisons with mapaddr.
* nscd/nscd-client.h: Include <time.h>.
* sysdeps/mach/hurd/dl-sysdep.c (fmh): Pass vm_offset_t dummy
9th parameter to __vm_region instead of int.
Joseph Myers [Wed, 18 Mar 2015 17:05:38 +0000 (17:05 +0000)]
Make sem_timedwait use FUTEX_CLOCK_REALTIME (bug 18138).
sem_timedwait converts absolute timeouts to relative to pass them to
the futex syscall. (Before the recent reimplementation, on x86_64 it
used FUTEX_CLOCK_REALTIME, but not on other architectures.)
Correctly implementing POSIX requirements, however, requires use of
FUTEX_CLOCK_REALTIME; passing a relative timeout to the kernel does
not conform to POSIX. The POSIX specification for sem_timedwait says
"The timeout shall be based on the CLOCK_REALTIME clock.". The POSIX
specification for clock_settime says "If the value of the
CLOCK_REALTIME clock is set via clock_settime(), the new value of the
clock shall be used to determine the time of expiration for absolute
time services based upon the CLOCK_REALTIME clock. This applies to the
time at which armed absolute timers expire. If the absolute time
requested at the invocation of such a time service is before the new
value of the clock, the time service shall expire immediately as if
the clock had reached the requested time normally.". If a relative
timeout is passed to the kernel, it is interpreted according to the
CLOCK_MONOTONIC clock, and so fails to meet that POSIX requirement in
the event of clock changes.
This patch makes sem_timedwait use lll_futex_timed_wait_bitset with
FUTEX_CLOCK_REALTIME when possible, as done in some other places in
NPTL. FUTEX_CLOCK_REALTIME is always available for supported Linux
kernel versions; unavailability of lll_futex_timed_wait_bitset is only
an issue for hppa (an issue noted in
<https://sourceware.org/glibc/wiki/PortStatus>, and fixed by the
unreviewed
<https://sourceware.org/ml/libc-alpha/2014-12/msg00655.html> that
removes the hppa lowlevellock.h completely).
In the FUTEX_CLOCK_REALTIME case, the glibc code still needs to check
for negative tv_sec and handle that as timeout, because the Linux
kernel returns EINVAL not ETIMEDOUT for that case, so resulting in
failures of nptl/tst-abstime and nptl/tst-sem13 in the absence of that
check. If we're trying to distinguish between Linux-specific and
generic-futex NPTL code, I suppose having this in an nptl/ file isn't
ideal, but there doesn't seem to be any better place at present.
It's not possible to add a testcase for this issue to the testsuite
because of the requirement to change the system clock as part of a
test (this is a case where testing would require some form of
container, with root in that container, and one whose CLOCK_REALTIME
is isolated from that of the host; I'm not sure what forms of
containers, short of a full virtual machine, provide that clock
isolation).
Tested for x86_64. Also tested for powerpc with the testcase included
in the bug.
[BZ #18138]
* nptl/sem_waitcommon.c: Include <kernel-features.h>.
(futex_abstimed_wait)
[__ASSUME_FUTEX_CLOCK_REALTIME && lll_futex_timed_wait_bitset]:
Use lll_futex_timed_wait_bitset with FUTEX_CLOCK_REALTIME instead
of lll_futex_timed_wait.
Brad Hubbard [Wed, 18 Mar 2015 09:21:26 +0000 (14:51 +0530)]
Use calloc to allocate xports (BZ #17542)
If xports is NULL in xprt_register we malloc it but if sock >
_rpc_dtablesize() that memory does not get initialised and may in theory
contain any value. Later we make a conditional jump in svc_getreq_common
based on the uninitialised memory and this caused a general protection
fault in rpc.statd on an older version of glibc but this code has not
changed since that version.
Following is the valgrind warning.
==26802== Conditional jump or move depends on uninitialised value(s)
==26802== at 0x5343A25: svc_getreq_common (in /lib64/libc-2.5.so)
==26802== by 0x534357B: svc_getreqset (in /lib64/libc-2.5.so)
==26802== by 0x10DE1F: ??? (in /sbin/rpc.statd)
==26802== by 0x10D0EF: main (in /sbin/rpc.statd)
==26802== Uninitialised value was created by a heap allocation
==26802== at 0x4C2210C: malloc (vg_replace_malloc.c:195)
==26802== by 0x53438BE: xprt_register (in /lib64/libc-2.5.so)
==26802== by 0x53450DF: svcudp_bufcreate (in /lib64/libc-2.5.so)
==26802== by 0x10FE32: ??? (in /sbin/rpc.statd)
==26802== by 0x10D13E: main (in /sbin/rpc.statd)
[BZ #17090]
[BZ #17620]
[BZ #17621]
[BZ #17628]
* NEWS: Update.
* elf/dl-tls.c (_dl_update_slotinfo): Clean up outdated DTV
entries with Static TLS too. Skip entries past the end of the
allocated DTV, from Alan Modra.
(tls_get_addr_tail): Update to glibc_likely/unlikely. Move
Static TLS DTV entry set up from...
(_dl_allocate_tls_init): ... here (fix modid assertion), ...
* elf/dl-reloc.c (_dl_nothread_init_static_tls): ... here...
* nptl/allocatestack.c (init_one_static_tls): ... and here...
* elf/dlopen.c (dl_open_worker): Drop l_tls_modid upper bound
for Static TLS.
* elf/tlsdeschtab.h (map_generation): Return size_t. Check
that the slot we find is associated with the given map before
using its generation count.
* nptl_db/db_info.c: Include ldsodefs.h.
(rtld_global, dtv_slotinfo_list, dtv_slotinfo): New typedefs.
* nptl_db/structs.def (DB_RTLD_VARIABLE): New macro.
(DB_MAIN_VARIABLE, DB_RTLD_GLOBAL_FIELD): Likewise.
(link_map::l_tls_offset): New struct field.
(dtv_t::counter): Likewise.
(rtld_global): New struct.
(_rtld_global): New rtld variable.
(dl_tls_dtv_slotinfo_list): New rtld global field.
(dtv_slotinfo_list): New struct.
(dtv_slotinfo): Likewise.
* nptl_db/td_symbol_list.c: Drop gnu/lib-names.h include.
(td_lookup): Rename to...
(td_mod_lookup): ... this. Use new mod parameter instead of
LIBPTHREAD_SO.
* nptl_db/td_thr_tlsbase.c: Include link.h.
(dtv_slotinfo_list, dtv_slotinfo): New functions.
(td_thr_tlsbase): Check DTV generation. Compute Static TLS
addresses even if the DTV is out of date or missing them.
* nptl_db/fetch-value.c (_td_locate_field): Do not refuse to
index zero-length arrays.
* nptl_db/thread_dbP.h: Include gnu/lib-names.h.
(td_lookup): Make it a macro implemented in terms of...
(td_mod_lookup): ... this declaration.
* nptl_db/db-symbols.awk (DB_RTLD_VARIABLE): Override.
(DB_MAIN_VARIABLE): Likewise.
Carlos O'Donell [Fri, 13 Mar 2015 13:49:24 +0000 (09:49 -0400)]
Enhance nscd's inotify support (Bug 14906).
In bug 14906 the user complains that the inotify support in nscd
is not sufficient when it comes to detecting changes in the
configurationfiles that should be watched for the various databases.
The current nscd implementation uses inotify to watch for changes in
the configuration files, but adds watches only for IN_DELETE_SELF and
IN_MODIFY. These watches are insufficient to cover even the most basic
uses by a system administrator. For example using emacs or vim to edit
a configuration file should trigger a reload but it might not if
the editors use move to atomically update the file. This atomic update
changes the inode and thus removes the notification on the file (as
inotify is based on inodes). Thus the inotify support in nscd for
configuration files is insufficient to account for the average use
cases of system administrators and users.
The inotify support is significantly enhanced and described here:
https://www.sourceware.org/ml/libc-alpha/2015-02/msg00504.html
Tested on x86_64 with and without inotify support.
Joseph Myers [Thu, 12 Mar 2015 18:43:21 +0000 (18:43 +0000)]
soft-fp: Define and use _FP_STATIC_ASSERT.
This patch makes soft-fp use static assertions in place of conditional
calls to abort, in places where there are checks for conditions (on
the types for which a macro is used) that the code is not prepared to
handle. The fallback definition of _FP_STATIC_ASSERT (for kernel use
only, as only relevant to compilers not supported for building glibc)
is as in misc/sys/cdefs.h.
This means that soft-fp only ever calls abort for _FP_UNREACHABLE
calls in builds with GCC versions before 4.5. Thus, there is no need
for an abort declaration or <stdlib.h> include, since the kernel code
handles defining abort as a macro itself - and so this avoids any need
for an __KERNEL__ condition on the abort declaration to avoid it
breaking with the kernel's macro definition. That is, this patch is
intended to make glibc's soft-fp code suitable for kernel use with no
kernel-local changes to the soft-fp code needed at all.
Tested for powerpc-nofpu that installed stripped shared libraries are
unchanged by the patch. One explicit <stdlib.h> include had to be
added to a file that was relying on the include from soft-fp.h.
* soft-fp/soft-fp.h (_FP_STATIC_ASSERT): New macro.
[_LIBC]: Do not include <stdlib.h>.
[!_LIBC] (abort): Remove declaration.
* soft-fp/op-2.h (_FP_MUL_MEAT_2_120_240_double): Use
_FP_STATIC_ASSERT instead of conditionally calling abort.
* soft-fp/op-common.h (_FP_FROM_INT): Likewise.
(_FP_EXTEND_CNAN): Likewise.
(FP_TRUNC): Likewise.
(__FP_CLZ): Likewise.
* sysdeps/powerpc/nofpu/flt-rounds.c: Include <stdlib.h>.
Aurelien Jarno [Thu, 12 Mar 2015 01:03:50 +0000 (21:03 -0400)]
Fix ldconfig segmentation fault with corrupted cache (Bug 18093).
ldconfig is using an aux-cache to speed up the ld.so.cache update. It
is read by mmaping the file to a structure which contains data offsets
used as pointers. As they are not checked, it is not hard to get
ldconfig to segfault with a corrupted file. This happens for instance if
the file is truncated, which is common following a filesystem check
following a system crash.
This can be reproduced for example by truncating the file to roughly
half of it's size.
There is already some code in elf/cache.c (load_aux_cache) to check
for a corrupted aux cache, but it happens to be broken and not enough.
The test (aux_cache->nlibs >= aux_cache_size) compares the number of
libs entry with the cache size. It's a non sense, as it basically
assumes that each library entry is a 1 byte... Instead this commit
computes the theoretical cache size using the headers and compares it
to the real size.
With AIX port deprecated there is no need to check/define
HAVE_ASM_GLOBAL_DOT_NAME anymore since the current minimum binutils
supported (2.22) does not emit global symbol with dot.
This patch removes all the HAVE_ASM_GLOBAL_DOT_NAME definition and
checks for powerpc64 port.
The constraints in the inline assembly in feholdexcept and fesetenv
are incorrect. The assembly modifies the buffer pointer, but doesn't
express that in the constraints. The simple fix is to remove the
modification of the buffer pointer which is no longer required by
the existing code, and adjust the one constraint that did express
the modification of bufptr.
The change fixes test-fenv when glibc is compiled with recent gcc.
Joseph Myers [Wed, 11 Mar 2015 01:14:15 +0000 (01:14 +0000)]
soft-fp: Add _FP_UNREACHABLE.
This patch makes soft-fp use a new macro _FP_UNREACHABLE in place of
calling abort in unreachable default cases of switch statements.
_FP_UNREACHABLE expands to call __builtin_unreachable for GCC 4.5 and
later; the fallback to abort is thus only for kernel use.
Tested for powerpc-nofpu that installed stripped shared libraries are
unchanged by this patch. Also tested with the math/ tests for mips64
(in the case of fma there *was* previously an abort call generated,
unlike for the other operations - one switch only deals with a subset
of classes for one operand based on what could have been generated in
the earlier part of fma, whereas the other switches deal with all
combinations of two classes - and this is apparently too complicated
for the default case to have been optimized away).
* soft-fp/soft-fp.h (_FP_UNREACHABLE): New macro.
* soft-fp/op-common.h (_FP_MUL): Use _FP_UNREACHABLE instead of
abort.
(_FP_FMA): Likewise.
(_FP_DIV): Likewise.
Joseph Myers [Tue, 10 Mar 2015 00:32:29 +0000 (00:32 +0000)]
soft-fp: Use multiple-include guards.
This patch makes soft-fp headers consistently use multiple-include
guards, something previously done mainly only in the Linux kernel
version. The guard macros aren't the same as those used in the Linux
kernel, but there seems to be enough variation in such guards in Linux
kernel code that hopefully this version will be acceptable there.
Tested for powerpc-nofpu that installed stripped shared libraries are
unchanged by this patch.
projects / thirdparty / glibc.git / log
